#include <stdio.h>



int main()
{
    int a,i,b,n;
    printf("There are following friendly - numbers pair smaller than 3000:\n");
    for(a = 1;a < 3000;a++)
    {
        for(b = 0,i = 1;i <= a/2;i++)
        {
            if(!(a%i))
            {
                b += i;
            }
        }
        for(n = 0,i = 1;i <= b/2;i++)
        {
            if(!(b%i))
            {
                n += i;
            }
        }
        if(n == a && a < b)
        {
            printf("%4d.. %4d\t",a,b);
        }
    }

    return 0;
}
//熊贤豪